This is an application for continuation of the Pulmonary Vascular Disease SCOR grant entitled, "Pathophysiology of Pulmonary Edema" (HL 19155-04). We are continuing animal studies on pulmonary fluid and protein exchanges as related to possible specific contribution of microemboli in pulmonary edema. We are continuing animal studies on the distribution of plasma proteins within the lung's interstitium and lymphatics. We are applying and comparing the results of new diagnostic methods with clinical and laboratory data obtained in a wide variety of patients with suspected and documented pulmonary edema (cardiogenic and noncardiogenic) to establish the relative usefulness of the various methods. We are following the natural history and effects of therapeutic regimes on early (interstitial) and late (alveolar) pulmonary edema. To accomplish these objectives we are using both acute, anesthetized and chronic, unanesthetized sheep with lung lymph fistulas and protein autoradiographic techniques in rats. For human studies we have established a two-bed pulmonary edema research unit for the specific application of currently available and newly-developed diagnostic methods and treatment regimes.